Pairing bluetooth device for just audio

How can I go about pairing my bluetooth headphones just for audio? When you pair a device it shows as connecting for both voice and audio separately, how do I turn off the connection for voice and keep audio? I've accidentally gotten it the other way around before.
The reason I need this done is because Cortana interrupts music with every text message I receive when connected to phone. I want to avoid this. Thanks in advance.

You can not select/edit what BT profiles are connected. This is the built into the hardware.
If you had given the OS your have on the phone I could have given how to turn can turn off announcing text message announcing over BT